Can I take my grandmother somewhere for bathing?

Depending on the issue - mobility ? Reluctance ? Access ?

You might be able to get a CNA to come to
Her home to bathe her 2x a week

Where I live they offer tub baths as part of the senior's day care programme, you could check about that. If accessibility is the problem some people have mostly made due with waterless shampoos and sponge bathes and then used the showers at their gym or in the handicapped suite of a hotel to get a good scrub occasionally.

The bathroom? Not following this question really.